The most relevant facts about overtraining

Overtraining occurs when an athlete is training vigorously but performance
is not getting better but deteriorates. In spite of yearlong research,
it is still not possible to diagnose overtraining reliably with a simple
test. One has to rely on a list of criteria and the analysis of the recent
training history of the athlete.

Low cortisol and catecholamine values and reduced or no response of free
cortisol to exercise are one of the signs of overtraining. However, it
is not reliable and consistent. Latest research suggests that overtraining
is best described as a systemic inflammation reaction.

The therapy consists of total rest or low intensity workout in a different
sport. Regeneration can take as much as weeks and months. Prevention includes
careful planning, performance monitoring of training and competition performance,
and communication with coach and physician.

Background of Overtraining

60 years ago Hans Seyle noted that stress could not only protect but
also damage the body. Since then the mechanisms responsible for the negative
stress reaction produced by excessive physical stress have been examined
carefully. It was found that the underlying mechanisms are associated
with the neural and hormone system, in particular the hypothalamic-pituitary-adrenal
axis. Sport can result in a positive health effect if the load for the
body does not exceed individual tolerance. The positive effect includes
positive mood control, increased immune function, weight control, protection
against increased weight, diabetes, cancer and cardiovascular disease,
osteoporosis, just to name a few effects. Sport is the base for a healthy
life style and prolonged life without disease and ailment.

Diagnosis of Overtraining

In spite of the yearlong research it is still not possible to make out
warning signs of overtraining early enough. Even the diagnosis of an acute
overtraining is not simple. One has to rely on a list of criteria and
symptoms. The trainings diary and development of recent training and competition
performance as well as observations made by the coach are important information
to discuss the issue with a sports physician. Table 1 shows the major
symptoms and signs of overtraining.

An important sign to diagnose overtraining is
the lack of or reduced increase of stress hormones during and following
exercise. Cortisol, adrenaline and noradrenaline belong to the stress hormones.
In particular, free cortisol measured in saliva does nit increase in overtrained
athletes. The characteristics are, however, neither reliable nor consistent
to diagnose overtraining.

Causes of Overtraining

Overtraining is caused by continuous and repeated training units that are
to intense and/or too extensive in combination with too little rest. Graph
(B) in figure 1 shows the decline in performance over time schematically.
Time for recovery is too short.

Correctly designed training and recovery lead to improved performance over
time (graph A).

Latest research shows that overtraining is a whole-body
inflammation. Typically, hormone-type substances, known as cytokines that
are released during inflammation, increase in overtrained athletes. If you
are interested in this topic there is a lecture that explains this in more
details ("Sports
and Immunology").

Exercise at moderate intensity is thought to have an anti-inflammatory effect
(Petersen and Pedersen, 2004). Overtraining, however, is possibly the result
or the symptom of a generalised inflammation. Tiny damage to muscle and
connective tissue known as microtrauma provoke this systemic inflammatory
reaction.